The invention relates to the field of combustion engines and, particularly, to an exhaust apparatus for placement in the exhaust stream of a combustion engine for improving the efficiency of the engine and for reducing pollutants in the exhaust stream.
Several devices have been disclosed with the purpose of improving operating efficiency and/or reducing pollutants in the exhaust gas issuing from a combustion engine, particularly the engine of an automobile or other vehicle.
U.S. Pat. No. 4,012,907 to Crayton discloses an example of such an apparatus for attachment to an exhaust pipe. The device comprises a generally tubular housing open at both ends and containing two blades rotatably mounted on an axle within the housing. The housing is larger than the exhaust pipe to which it is to be attached so that external air can enter the leading open end and contact the blades so as to drive the blades and operate the mechanism. Obviously, the drive structure of this device results in openings in the exhaust conduit and the undesirable potential for flow out of the exhaust pipe, particularly when the vehicle to which the device is attached is not moving. Further, the device must apparently be positioned at the end of the exhaust pipe.
It is desirable to provide an apparatus which effectively provides drive of a fan without breaking the integrity of the exhaust conduit, and which enhances removal of pollutants from the exhaust stream.
It is therefore the primary object of the present invention to provide an apparatus for improving the efficiency of a combustion engine by improving the extraction of exhaust gas from the exhaust system of the engine.
It is another object of the invention to provide such an apparatus which is partially driven by the exhaust gas stream of the engine.
It is still another object of the present invention to provide an apparatus with a simple and effective supplemental drive which serves to enhance scavenging of exhaust gasses from the combustion chamber.
It is a further object of the invention to provide such an apparatus which reduces the pollutants present in the exhaust stream.
It is a still further object of the invention to provide an apparatus as above which can readily be installed at a desired location of the exhaust system of a combustion engine, either as an after-market device or, alternatively, as a factory installed device.
Other objects and advantages will appear hereinbelow.